This invention relates generally to improved processes and apparatus for developing and handling wound coils for use in electromagnetic devices and, more particularly, to new and improved apparatus and methods that are of particular value when machine set-up changes should be effected so as to produce inductive devices having differing design specifications.
The present invention also relates to improved apparatus and methods for interdependently conditioning winding turn generating apparatus and winding turn placing apparatus, so that such apparatus may be readily and quickly utilized in the production of wound electromagnetic devices of differing designs.
Apparatus and methods for developing wound coils for use in electromagnetic devices, and particularly for dynamoelectric machines (e.g. electric motors) are highly developed in the art, as are equipment and processes for axially placing or injecting prewound coils into the slots of magnetic cores. Cutler et al. U.S. Pat. No. Re. 27,415 and Lauer U.S. Pat. No. 3,765,080 are two patents that represent the state of development (as of their respective filing dates) of the winding equipment and winding method art. Methods that are of particular use for axially inserting coils in magnetic cores are exemplified, for example, in the expired A. P. Adamson U.S. Pat. No. 3,432,267; Hill U.S. Pat. No. 3,508,316; and Arnold U.S. Pat. No. 3,722,063.
Particularly significant advances in the coil placing art are represented in the previously referenced co-pending application and Smith U.S. Pat. No. 3,698,063. For example, when following the teachings presented therein, quick and easy changes in set-up of coil placing equipment may be effected. As pointed out in the above-referenced co-pending application and patent, the types of equipment that were known long prior to the present application required the extensive utilization of labor to make equipment changes (when such changes were feasible at all) in order to accommodate changes in the axial height of the core.
Efforts also have been made to provide winding forms (sometimes also called winding molds) which could be adjusted so as to provide windings (composed of one or more coils each having one or more turns) of conductive material that could be placed into cores of different axial heights. Arnold U.S. Pat. No. 3,672,027 (issued June 27, 1972), for example, teaches how this may be accomplished. However, it has continued to be necessary to independently adjust or change the set-up of both winding coil producing equipment and coil placing equipment. It thus will be understood that it would be particularly desirable to provide means and methods for interdependently conditioning winding coil producing equipment and winding coil placing equipment so that winding coils for cores of different axial lengths may be expeditiously produced and placed on such cores.
As above noted, prior winding equipment has been provided with means for adjusting the size of coils (i.e., the mean turn length or turn circumference) so as to permit the production of coils for cores of differing stack heights. However, problems associated with changing the "span of wound coils" have not been solved. Heretofore, it has been necessary to actually use a first set of winding "forms" or "molds" in order to produce coils that would span an "even" number of core teeth and then use a second set of forms or molds in order to produce coils that would span an "odd" number of core teeth. Accordingly, it would be desirable to provide means and methods whereby winding coils of both even and odd span could be produced with a single set of turn establishing means (e.g., a single form or mold set).
In order to better explain the reason for the odd or even "span" problem, it is noted that cores for motors, for example, may be designed to have a given stack height, a give bore, and a given number of "slots" or "teeth". It may be desired to place windings in these slots that will provide two different operational speeds, or to make one set of motors to operate at a first speed and a second set of motors to operate at a second, different speed.
For example, a motor having a stator core with 36 teeth (and thus 36 winding accommodating slots) may be provided with both a four-pole main winding and an eight-pole main winding. In a situation such as this, the eight pole main winding may be made up of some coil groups which have at least one coil spanning an odd number of core teeth, and some coil groups which have at least one coil that spans an even number of core teeth. When teachings of the present application are utilized, successive "odd span" and "even span" coil groups may be produced on a given piece of winding equipment in a rapid and efficient manner.